Surgical instruments with non-contact switch assemblies

ABSTRACT

A non-contact button assembly for a powered surgical instrument includes a light emitter, a rocker switch, and a button shaft. The rocker switch defines a through passage about a longitudinal axis of the button assembly. The button shaft is disposed within the through passage. The button shaft includes a proximal portion, a distal portion, and a flange positioned therebetween. The button shaft has a deactivated position such that the button shaft is configured to prevent light from the light emitter from illuminating a light detector and the button shaft has an activated position such that the button shaft is configured to permit light emitted from the light emitter to illuminate the light detector.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.14/523,399, filed Oct. 24, 2014, which claims the benefit of andpriority to U.S. Provisional Patent Application No. 61/939,987, filedFeb. 14, 2014. The entire contents of each of these applications arehereby incorporated by reference.

BACKGROUND

1. Technical Field

The present disclosure relates to surgical instruments and, morespecifically, to powered surgical instruments including non-contactswitch block assemblies.

2. Discussion of Related Art

Powered surgical instruments generally have a handle portion including aplurality of control buttons and switches to control electricalcomponents within the handle portion and a working portion extendingfrom the handle portion that contacts a patient. After each use, thepowered surgical instrument is disposed of, reused, or partiallydisposed of and partially reused. Any part of a powered surgicalinstrument that is reused must be sterilized to neutralize potentiallyinfectious agents before being reused.

The autoclave process has been used for many years to sterilizedreusable surgical instruments. However, the steam and the high-pressureused in the autoclave process can damage electrical components withinthe housing.

The plurality of control buttons and switches must be able to withstandrepeated exposure to the autoclave process. A common solution is to sealthe plurality of control buttons and switches or cover the plurality ofcontrol buttons and switches with membranes. However, cyclicpressurizing and depressurizing of the plurality of control buttons andswitches fatigue the seals or membranes. As a consequence of thisfatigue, steam can enter the plurality of control buttons and switchescausing the powered surgical instrument to fail.

Accordingly, a continuing need exists for control buttons and switchesthat can withstand cyclical pressurizing and depressurizing.

SUMMARY

In an aspect of the present disclosure, a non-contact button assemblyfor a powered surgical instrument includes a light emitter configured toemit light, a light detector, a rocker switch, a rocker housing, abutton retainer, and a button shaft. The rocker switch has a proximalend portion and defines a through passage about a longitudinal axisthereof through the proximal end portion. The rocker housing ispositioned about the proximal end portion of the rocker switch to retainthe rocker switch within the rocker housing. The button shaft isdisposed within the through passage of the rocker switch and includes aproximal portion, a distal portion, and a flange positioned between theproximal and distal portions. The button shaft has a deactivatedposition such that the button shaft is configured to prevent light fromthe light emitter from illuminating the light detector and the buttonshaft has an activated position such that the button shaft is configuredto permit light emitted from the light emitter to illuminate the lightdetector.

In embodiments, the button shaft defines a through slot orthogonal to alongitudinal axis thereof. In such embodiments, the through slot may bealigned with the light emitter in the activated position and offset fromthe light emitter in the deactivated position. The through slot may bepositioned distal to the flange.

In some embodiments, the proximal portion of the button shaft defines anopening and the light emitter is positioned within the opening. Thelight emitter may be configured to emit light from the opening towardsthe light detector. A cover may be coupled to the proximal portion ofthe button shaft adjacent the opening. In a closed configuration of thecover, the cover is configured to prevent light from the light emitterfrom illuminating a light detector and in an open configuration of thecover, the cover is configured to permit light to illuminate the lightdetector. The cover may include a tap extending beyond an outer surfaceof the proximal portion of the button shaft that is configured to engagethe rocker housing to transition the cover to the open position when thebutton shaft is in the activated position.

In embodiments, the button assembly further includes a control buttonsecured to the distal portion of the button shaft. The control buttonmay be threadably secured to the distal portion of the button shaft.

In some embodiments, the light emitter is a light pipe configured totransmit light from the light source. A light pipe may be configured totransmit light from the light emitter to illuminate a light detector.

In embodiments, the button assembly further includes a rocker disc and asecond light emitter. The rocker disc defines an activation slot andcooperates with the rotation of the rocker switch about the longitudinalaxis. In a deactivated position of the rocker switch, the second lightemitter is offset from the activation slot and the rocker disc preventslight emitted from the second light emitter from illuminating a lightdetector. In an activated position of the rocker disc, the second lightemitter is aligned with the activation slot to illuminate a lightdetector through the activation slot.

In preferred embodiments, the light emitter is configured to encodelight emitted therefrom and the detector is configured to selectivelyrespond to encoded signals.

In aspects of the present disclosure, a surgical handle includes ahandle housing, a control assembly, and a switch block assembly. Thecontrol assembly includes a first light detector sealed within thehandle housing and the switch block assembly includes a switch blockfixed to the handle housing. The switch block includes a firstnon-contact button assembly having a first light emitter configured toemit light. The first non-contact button assembly further includes arocker switch, a rocker housing, a button retainer, and a button shaft.The rocker switch includes a proximal end portion and defines a throughpassage through the proximal end portion about a longitudinal axisthereof. The rocker housing is positioned about the proximal end portionof the rocker switch and the button retainer is secured about theproximal end portion of the rocker switch to retain the rocker switchwithin the rocker housing. The button shaft is disposed within thethrough passage of the rocker switch. The button shaft has a proximalportion, a distal portion, and a flange positioned therebetween. Thebutton shaft has a deactivated position such that the button shaft isconfigured to prevent light from the light emitter from illuminating thefirst light detector and the button shaft has an activated position suchthat the button shaft is configured to permit light emitted from thelight emitter to illuminate the first light detector.

In embodiments, the handle includes a drive component operativelyassociated with the first light detector such that the control assemblyis configured to activate the drive component when the first lightdetector is illuminated by light emitted from the first light emitter.

In some embodiments, the handle housing is sealed from the switch blockand the control assembly includes a first light source positioned withinthe handle housing and the first light emitter includes a fiber opticlight pipe configured to receive light from the first light source.

In embodiments, the control assembly includes a second light detectorand the switch block includes a second non-contact button assembly. Thesecond non-contact button assembly includes a rocker switch, a rockerhousing, a button retainer, and a button shaft. The rocker switchincludes a proximal end portion positioned and defines a through passagethrough the proximal end portion about a longitudinal axis thereof. Therocker housing is positioned about the proximal end portion of therocker switch and the button retainer is secured about the proximal endportion of the rocker switch to retain the rocker switch within therocker housing. The button shaft is disposed within the through passageof the rocker switch. The button shaft has a proximal portion, a distalportion, and a flange positioned therebetween. The button shaft has adeactivated position such that the button shaft is configured to preventlight from the light emitter from illuminating the second light detectorand the button shaft has an activated position such that the buttonshaft is configured to permit light emitted from the light emitter toilluminate the second light detector. The first light detector may beconfigured to activate a drive component operatively associated with thefirst light detector when the first light detector is illuminated withlight emitted from the first light emitter. The first light detector maybe configured to not sense light emitted from the second light emittersuch that the first light detector does not activate the drive componentwhen illuminated by light from the second light emitter. In someembodiments, the control assembly includes third and fourth lightdetectors such that the rocker switch of the first non-contact controlbutton assembly is operatively associated with a third light emitter andthe rocker switch of the second non-contact control button assembly isoperatively associated with a fourth light emitter.

Further, to the extent consistent, any of the aspects described hereinmay be used in conjunction with any or all of the other aspectsdescribed herein.

BRIEF DESCRIPTION OF THE DRAWINGS

Various aspects of the present disclosure are described hereinbelow withreference to the drawings, wherein:

FIG. 1 is a perspective view of an exemplary powered surgical handle inaccordance with the present disclosure including a non-contact switchblock assembly;

FIG. 2 is an exploded view of the powered surgical handle of FIG. 1illustrating the components thereof;

FIG. 3 is an exploded view of the switch block assembly of FIG. 2illustrating the components thereof;

FIG. 4 is a side cross-sectional view of the surgical handle of FIG. 1taken along the longitudinal axis thereof;

FIG. 5 is an enlarged view of the detail area 5 of FIG. 4 showing acontrol switch assembly and a rocker switch in a deactivated position;

FIG. 6 is a side view of the control switch assembly and the rockerswitch of FIG. 5 in an activated position;

FIG. 7 is an enlarged view of the detail area 7 of FIG. 4 showing acontrol switch assembly and a rocker switch in a deactivated position;and

FIG. 8 is a side view of the control switch assembly and the rockerswitch of FIG. 7 in an activated position.

DETAILED DESCRIPTION

Embodiments of the present disclosure are now described in detail withreference to the drawings in which like reference numerals designateidentical or corresponding elements in each of the several views. Asused herein, the term “clinician” refers to a doctor, a nurse, or anyother care provider and may include support personnel. Throughout thisdescription, the term “proximal” refers to the portion of the device orcomponent thereof that is closest to the clinician and the term “distal”refers to the portion of the device or component thereof that isfurthest from the clinician.

Referring to FIG. 1, an exemplary embodiment of a surgical handle 100provided in accordance with the present disclosure. The surgical handle100 is a powered hand held electromechanical instrument configured forselective attachment thereto of a plurality of different end effectorsthat are each configured for actuation and manipulation by the poweredhand held electromechanical surgical instrument. An exemplary example ofsuch a powered hand held electromechanical surgical instrument isdisclosed in commonly owned and co-pending U.S. Pat. Nos. 8,968,276 and9,055,943, the contents of each being hereby incorporated by referencein its entirety.

As illustrated in FIGS. 1 and 2, the surgical handle 100 includes ahandle housing 102 having a lower housing portion 104, an intermediatehousing portion 106 extending from and/or supported on the lower housingportion 104, and an upper housing portion 108 extending from and/orsupported on the intermediate housing portion 106. The intermediate andupper housing portions 106, 108 are separated into a distal half-section110 a that is integrally formed with and extending from the lowerportion 104, and a proximal half-section 110 b connectable to the distalhalf-section 110 a by a plurality of fasteners. When joined, the distaland proximal half-sections 110 a, 110 b define a handle housing 102having a cavity 102 a therein in which a circuit board 150 and a drivemechanism 160 is situated.

The handle housing 102 includes a gasket 112 extending completely arounda rim of the distal half-section 110 a and/or proximal half-section 110b and being interposed between the distal and proximal half-sections 110a, 110 b. The gasket 112 seals the perimeter of the distal and proximalhalf-sections 110 a, 110 b. The gasket 112 functions to establish anairtight seal between the distal and proximal half-sections 110 a, 110 bsuch that the circuit board 150 and the drive mechanism 160 areprotected from sterilization and/or cleaning procedures.

The intermediate housing portion 106 of the handle housing 102 providesa housing in which the circuit board 150 is situated. The circuit board150 is configured to control the various operations of the surgicalhandle 100, as detailed below.

As shown, the lower housing portion 104 of the handle housing 102provides a housing in which a rechargeable battery (not shown) isremovably situated. The battery is configured to supply power to any ofthe electrical components of the surgical handle 100. The lower housingportion 104 defines a cavity (not shown) into which the battery isinserted. The lower housing portion 104 includes a door 105 pivotallyconnected thereto for closing the cavity of the lower housing portion104 and retaining the battery therein.

With reference to FIGS. 2 and 3, the handle housing 102 supports aswitch block assembly 10 on a distal surface or side of the intermediatehousing portion 106. The switch block assembly 10 includes a switchblock 11, a pair of button receiving holes 12, 13, and a pair offinger-actuated control button assemblies 20, 30 received within thebutton receiving holes 12, 13, respectively. The switch block 11 mayform an airtight seal between itself and the distal surface of theintermediate housing portion 106. The switch block 11 supports the pairof control button assemblies 20, 30. The button receiving holes 12, 13may be blind, stepped, or through holes. Each of the control buttonassemblies 20, 30 include a rocker switch 40. Each of the control buttonassemblies 20, 30 functions in a non-contact manner to control variousoperations of the surgical handle 100, as detailed below. It will beunderstood that the switch block 11 forms a seal with the intermediatehousing portion 106 and that the control button assemblies 20, 30operate in a non-contact manner to maintain the seal of the cavity 102 aduring surgical, sterilization, and/or cleaning procedures.

With reference to FIGS. 2 and 4, the handle 100 includes a controlassembly 50 disposed on the circuit board 150 having light emitters 52a-d and sensors 54 a-d. Each of the sensors 54 a-d operatively associatea respective one of the control button assemblies 20, 30 or rockerswitches 40 with one or more of the drive components of the handle 100.When the respective one of the control button assemblies 20, 30 orrocker switches 40 is in a deactivated position, light from therespective light emitter 52 a-d is prevented from contacting therespective one of the sensors 54 a-d. When the respective one of thecontrol button assemblies 20, 30 or rocker switches 40 is in anactivated position, light from the respective light emitter 52 a-d isreceived by the one of the respective sensors 54 a-d as detailed below.

The light emitted by each light emitter 52 a-d may be coded and/orencrypted to only one of the respective sensors 54 a-d such that whenlight from one light emitter 52 a-d illuminates a sensor 54 a-d notassociated with the respective one of the light emitters 52 a-d, thesensor 54 a-d does not activate a drive component(s) associated with therespective sensor 54 a-d as detailed below. In embodiments, each lightemitter 52 a-d emits light at a specific wavelength or wavelengthswithin the UV spectrum, the visible spectrum, or the IR spectrum toencode the light to one or more respective sensors 54 a-d. In someembodiments, each light emitter 52 a-d emits light in a specific patternto encode the light to a respective one of the sensors 54 a-d. It iscontemplated that one light emitter 52 a-d may emit light configured tobe received by more than one sensor 54 a-d or that one sensor 54 a-d maybe configured to activate a drive component in response to light emittedfrom more than one of the light emitters 52 a-d.

Each of the control button assemblies 20, 30 and rocker switches 40 areoperatively associated with one or more drive components of the handle100 (e.g., drive shafts 118, 122) in a non-contact manner. Each of thedrive components of the handle 100 controls a function of an endeffector (not shown) engaged directly with the handle 100, or indirectlywith the handle via an adapter (not shown). The functions of the endeffector engaged with the handle may include but are not limited toclamping tissue, articulating the end effector, rotating the endeffector, firing staples, firing a clip, forming a suture, cuttingtissue, etc. In the deactivated position, the drive componentoperatively associated with the control button assemblies 20, 30 androcker switches 40 is not actively driven by the handle 100. It iscontemplated that when a drive component is not actively driven by thehandle 100, that external forces on the end effector may result inmovement of the drive component (e.g., an end effector may articulatewhen contacting tissue which may result in rotation of the drivecomponent associated with articulation of the end effector). It isfurther contemplated that when a drive component is not actively driven,that the drive component is locked preventing movement of a component ofthe end effector (e.g., when an end effector contacts tissue the endeffector resists movement).

Referring now to FIGS. 3-5, the control button assembly 20 includes acontrol button 21, a rocker switch 40, a button shaft 22, abutton-biasing member 28, a pair of rocker-biasing members 44, a rockerhousing 46, a rocker disc 47, and a button retainer 29. The controlbutton 21 includes an engagement surface 21 a facing away from theswitch block 11 for selective activation of control button 21 and athreaded shaft 21 a extending towards the switch block 11. Theengagement surface 21 a of control button 21 may be convex, concave, ortextured to provide tactile feedback to the clinician as to which buttonis engaged. The button shaft 22 includes a distal portion 23, a proximalportion 26, and a flange 25 positioned between the distal and proximalportions 23, 26 of the button shaft 22. The distal portion 23 defines athreaded hole 24 that cooperates with the threaded shaft 21 b of thecontrol button 21 to secure the control button 21 to the distal portion23 of the button shaft 22. The threaded hole 24 may be a blind hole ormay extend through the button shaft 22. The flange 25 extends beyond theouter surface of the distal and proximal portions 23, 26 to prevent thebutton shaft 22 from passing through the rocker switch 40. The throughslot 27 is defined through the proximal portion 26 of the button shaft22, orthogonal to the longitudinal axis of the button shaft 22.

The rocker switch 40 defines a stepped through passage 41 and includes aproximal end portion 42 and an actuation arm 43. The distal portion 23of the button shaft 22 is received within the stepped through passage 41of the rocker switch 40 such that the button shaft 22 may longitudinallyslide relative to the rocker switch 40 and the rocker switch 40 mayrotate about the button shaft 22. The proximal end portion 42 passesthrough the rocker housing 46 and the rocker disc 47. The proximal endportion 42 defines a keyway 42 a parallel to the longitudinal axisthereof. The rocker disc 47 is disposed over the proximal end portion 42of the rocker switch 40 between the rocker housing 46 and the buttonretainer 29. The rocker disc 47 defines a central opening 48 thatincludes a key 48 a to radially align the rocker disc 47 with the rockerswitch 40. The rocker disc 47 further defines activation slots 49through the surfaces of the rocker disc 47 as detailed below. Theproximal end portion 42 of rocker switch 40 further defines a retaininggroove 42 b adjacent a proximal end thereof. The button retainer 29 isreceived within the retaining groove 42 b to secure the button assembly20 together.

The button-biasing member 28 engages the flange 25 to urge the buttonshaft 22 distally towards a deactivated position, i.e., away from or outof switch block 11. The button-biasing member 28 is disposed over theproximal portion 26 of the button shaft 22 between the flange 25 of thebutton shaft 22 and the retainer housing 46. The retainer housing 46includes a step 46 a to prevent the button-biasing member 28 frompassing through the retainer housing 46.

The pair of rocker-biasing members 44 urge the rocker switch 40 to aneutral or deactivated position. The pair of rocker-biasing members 44are disposed within an arcuate slot 45 of the rocker housing 46. Therocker switch 40 includes a biasing-protrusion 43 a positioned betweenthe pair of rocker-biasing members 44 within the arcuate slot 45. Eachof the pair of rocker-biasing members 44 engages the biasing-protrusion43 such that when no external force is applied to the rocker switch 40(e.g., a finger engaging the arm 43) the rocker-biasing members 44engage the biasing-protrusion 43 with equal force to urge the rockerswitch 40 to the deactivated position.

With reference to FIGS. 5 and 6, the control button 21 has a deactivatedposition (FIG. 5) and an activated position (FIG. 6). The light emitter52 a is positioned along the distal portion 23 of the button shaft 22such that light is emitted from the light emitter 52 a towards thebutton shaft 22. When the control button 21 is in the deactivatedposition (FIG. 4), the slot 27 is offset from the light emitter 52 asuch that light emitted from light emitter 52 a does not pass throughthe slot 27 to illuminate the sensor 54 a. When the control button 21 isdepressed against the button-biasing member 28 to the activated position(FIG. 5), the slot 27 is aligned with the light emitter 52 a such thatlight emitted from the light emitter 52 a passes through the slot 27 toilluminate the sensor 54 a. As detailed above, when the light emitter 52a illuminates the sensor 54 a, the sensor 54 a sends a signal toactivate one or more drive component(s) associated with sensor 54 a. Itis also contemplated that in the deactivated position the light emitter52 a may illuminate the sensor 54 a and in the activated position thelight emitter 52 a is prevented from illuminating the sensor 54 a (e.g.,the slot 27 is aligned with the light emitter 52 a in the deactivatedposition and offset from the light emitter 52 a in the activatedposition).

With continued reference to FIGS. 5 and 6, the rocker switch 40 has adeactivated position (FIG. 5) and an activated position (FIG. 6). Thelight emitter 54 b is positioned about the rocker disc 47 such thatlight emitted from the light emitter 54 b is directed towards the rockerdisc 47 and the sensor 54 b. When the rocker switch 40 is in thedeactivated position (FIG. 5), the activation slots 49 are offset fromthe light emitter 54 b with the rocker disc 47 preventing the lightemitter 54 b from illuminating the sensor 54 b. When the rocker switch40 is rotated about the button shaft 22 to the activated position (FIG.5), one of the activation slots 49 is aligned with the light emitter 52b to permit light from the light emitter 52 b to pass through one of theactivation slots 49 to illuminate the sensor 54 b. One of the activationslots 49 may include a film or filter 49 a to alter the light emittedfrom source 52 b to encrypt the light illuminating sensor 54 b toindicate which one of the activation slots 49 b is aligned with thelight emitter 52 b. It is contemplated, that the filter 49 a may allowthe sensor 54 b to activate the drive component in a particulardirection (e.g., if the drive component is for articulation, the filter49 a may alter the light emitted form the light emitter 52 b to indicatethat the rocker switch 40 was rotated clockwise to articulate an endeffector (not shown) to the right and unaltered light from the lightemitter 52 b indicates that the rocker switch 40 was rotatedcounter-clockwise to articulate the end effector to the left). It iscontemplated that slot 27 may include a similar film or filter to alteror encrypt light emitted from a respective one of the light emitters 52a-d.

It is also contemplated that activation slots 49 may be disposed aboutthe perimeter of the rocker disc 47 such that as the rocker disc 47 isrotated from the deactivated position towards the activated position,the amount of light illuminating the sensor 54 b increases as the rockerdisc 47 approaches the activated position. The sensor 54 b is configuredto detect the increased amount of light (e.g., intensity) to increasethe energy sent to a drive component operatively associated with thesensor 54 b (e.g., increase a rotational speed or torque supplied to thedrive component). It is also contemplated that film 49 a may vary thelight passing through the activation slot 49 as the rocker disc 47 isrotated to change a property of the light (e.g., the wave length, theintensity, etc.) to increase or decrease the energy sent to a drivecomponent operatively associated with the sensor 54 b.

Referring now to FIGS. 3, 4, and 7, the button assembly 30 includes acontrol button 31, a rocker switch 40, a button shaft 32, abutton-biasing member 38, a pair of rocker-biasing members 44, a rockerhousing 46, a rocker disc 47, and a button retainer 39. The controlbutton 31, switch biasing-member 38, and button retainer 39 of theswitch assembly 30 are substantially similar to the control button 21,switch biasing-member 28, and button retainer 29 of the switch assembly20 detailed above, as such only the differences and the relation withother components of the button assembly 30 will be detailed herein.

The button shaft 32 includes a distal portion 33, a proximal portion 36,and a flange 35 positioned between the distal and proximal portions 33,36. The distal portion 33 defines a threaded hole 34 that cooperateswith a threaded shaft 31 b of the control button 31 to secure thecontrol button 31 to the distal portion 33 of the button shaft 32. Thethreaded hole 34 may be a blind hole or may extend through the buttonshaft 32. The flange 35 extends beyond the outer surface of the distaland proximal portions 33, 36 to prevent the button shaft 32 from passingthrough the rocker switch 40.

The proximal end of the proximal portion 36 defines an opening 37. Theopening 37 may form a through hole with threaded hole 34 that passesthrough the button shaft 32. A light emitter 52 c is positioned withinthe opening 37. The button assembly 30 further includes a cover 37 aadjacent opening 37.

With reference to FIGS. 7 and 8, the cover 37 has a closed condition(FIG. 7) and an open condition (FIG. 8) corresponding to the deactivatedposition and the activated position, respectively. In the closedcondition, the cover 37 prevents light from the light emitter 52 c fromexiting the opening 37 and in the open condition, light from lightemitter 52 c exits the opening 37 to illuminate a sensor 54 c. The cover37 a is coupled about the proximal end of the proximal portion 36 andincludes a tab 37 b extending radially therefrom. As the button 31 isdepressed, the tab 37 b engages the rocker housing 46 to transition thecover 37 a to the open condition. In embodiments, the cover 37 aincludes two halves overlapping along a centerline of the cover 37 awith each half of the cover 37 a including a tab 37 b.

The light emitter 52 c is positioned within the opening 37 as detailedabove. The sensor 54 c is aligned with the light emitter 52 c such thatlight emitted from the opening 37 will illuminate the sensor 54 c. Asshown, sensor 54 c is aligned with the longitudinal axis of the buttonshaft 33; however, it is contemplated that the sensor 54 c may be offsetfrom the longitudinal axis of the button shaft 33 and a surface of thecover 37 a may deflect light towards the sensor 54 c. In the deactivatedposition (FIG. 7), the cover 37 a is in the closed condition preventinglight from the light emitter 52 c from illuminating the sensor 52 c.When the control button 31 is depressed against the button-biasingmember 38 to the activated position (FIG. 8), the tab 37 b of the cover37 a engages a portion of the retainer housing 46 to transition thecover 37 a to the open condition permitting light emitting from thelight emitter 52 c to illuminate the sensor 52 c.

With reference to FIGS. 5-8, each light emitter 52 a-d may beoperatively associated with a light source 58 a-d by a light pipe 56a-d. For example, with particular reference to FIG. 5, the light emitter52 b may be operatively associated with a light source 58 b by a lightpipe 56 b passing through a portion of the switch block 11. The lightpipe 56 b may be a fiber optic cable with one end positioned adjacentthe light source 58 b and the other end positioned adjacent the lightemitter 52 b. It is also contemplated that the light emitter 52 b isintegrally formed with one end of the light pipe 56 b. It is alsocontemplated that a light pipe (e.g., light pipe 56 a) may be configuredto transmit received from a light emitter to a light detector (e.g.,light detector 54 a).

It will be understood that the operation of the rocker switch 40associated with button assembly 30 is similar to the operation of therocker switch 40 associated with button assembly 20; as such theoperation of the rocker switch 40 associated with button assembly 20will not be detailed below for reasons of brevity.

While several embodiments of the disclosure have been shown in thedrawings, it is not intended that the disclosure be limited thereto, asit is intended that the disclosure be as broad in scope as the art willallow and that the specification be read likewise. Any combination ofthe above embodiments is also envisioned and is within the scope of theappended claims. Therefore, the above description should not beconstrued as limiting, but merely as exemplifications of particularembodiments. Those skilled in the art will envision other modificationswithin the scope and spirit of the claims appended hereto.

1-17. (canceled)
 18. A non-contact button assembly for a poweredsurgical instrument, the button assembly comprising: a first lightemitter; a button shaft having a proximal portion, a distal portion, anda flange positioned between the proximal and distal portions, theproximal portion defining an opening, the first light emitter positionedwithin the opening and configured to emit light from the opening; and acover coupled to the proximal portion of the button shaft adjacent theopening, the cover having a closed configuration in which the cover isconfigured to prevent light from the first light emitter fromilluminating a light detector, and an open configuration in which thecover is configured to permit light from the first light emitter toilluminate a light detector.
 19. The non-contact button assemblyaccording to claim 18, wherein the button shaft has a deactivatedposition in which the cover is in the closed configuration and anactivated position in which the cover is in the open configuration. 20.The non-contact button assembly according to claim 19, wherein thebutton shaft is configured to be depressed for actuation from thedeactivated position to the activated position.
 21. The non-contactbutton assembly according to claim 20, wherein the button shaft isbiased towards the deactivated position.
 22. The non-contact buttonassembly according to claim 18, wherein the cover includes a tabextending beyond an outer surface of the proximal portion, the tabconfigured to transition the cover to the open position upon movement ofthe button shaft from the deactivated position to the actuated position.23. The non-contact button assembly according to claim 18, wherein thefirst light emitter is a light pipe configured to transmit light from alight source.
 24. The non-contact button assembly according to claim 18,further comprising a light pipe configured to direct light from thefirst light emitter towards a light detector.
 25. The non-contact buttonassembly according to claim 18, wherein the first light emitter isconfigured to encode light emitted therefrom.
 26. The non-contact buttonassembly according to claim 18, further comprising: a second lightemitter; and a switch rotatably disposed about the button shaft, theswitch including a disc defining an activation slot, the switch having afirst radial position in which the disc is configured to prevent lightfrom the second light emitter from illuminating a light detector and asecond radial position in which the activation slot is aligned with thesecond light emitter such that the second light emitter is configured toilluminate a light detector.
 27. A surgical instrument comprising: ahousing; a tool assembly configured to act on tissue; and a controlassembly configured to manipulate the tool assembly, the controlassembly including: a first light detector disposed within the housing;and a first non-contact button assembly having: a first light emitter; abutton shaft having a proximal portion, a distal portion, and a flangepositioned between the proximal and distal portions, the proximalportion defining an opening, the first light emitter positioned withinthe opening and configured to emit light from the opening; and a covercoupled to the proximal portion of the button shaft adjacent theopening, the cover having a closed configuration in which the coverprevents light from the first light emitter from illuminating the firstlight detector and an open configuration in which the cover permitslight from the first light emitter to illuminate the first lightdetector.
 28. The surgical instrument according to claim 27, wherein thebutton shaft of the control assembly has a deactivated position in whichthe cover is in the closed configuration and an activated position inwhich the cover is in the open configuration.
 29. The surgicalinstrument according to claim 28, wherein the button shaft of thecontrol assembly is configured to be depressed for actuation from thedeactivated position to the activated position.
 30. The surgicalinstrument according to claim 29, wherein the button shaft of thecontrol assembly is biased towards the deactivated position.
 31. Thesurgical instrument according to claim 27, wherein the cover of thecontrol assembly includes a tab extending beyond an outer surface of theproximal portion, the tab engaging a portion of the housing totransition the cover to the open position upon movement of the buttonshaft from the deactivated position to the activated position.
 32. Thesurgical instrument according to claim 27, wherein the first lightemitter of the control assembly is a light pipe configured to transmitlight from a light source disposed within the housing.
 33. The surgicalinstrument according to claim 27, wherein the control assembly furthercomprises a light pipe configured to direct light from the first lightemitter towards the first light detector.
 34. The surgical instrumentaccording to claim 27, wherein the first light emitter of the controlassembly is configured to encode light emitted therefrom.
 35. Thesurgical instrument according to claim 27, wherein the control assemblyfurther includes: a second light emitter; and a switch rotatablydisposed about the button shaft, the switch including a disc defining anactivation slot, the switch having a first radial position in which thedisc prevents light from the second light emitter from illuminating thefirst light detector and a second radial position in which theactivation slot is aligned with the second light emitter such that thesecond light emitter illuminates the first light detector.
 36. Thesurgical instrument according to claim 35, wherein the first lightdetector of the control assembly is configured to differentiate betweenlight emitted from the first light emitter and light emitted from thesecond light emitter.
 37. The surgical instrument according to claim 27,wherein the control assembly further comprises: a second light detectordisposed within the housing; a second light emitter; and a switchrotatably disposed about the button shaft, the switch including a discdefining an activation slot, the switch having a first radial positionin which the disc prevents light from the second light emitter fromilluminating the second light detector and a second radial position inwhich the activation slot is aligned with the second light emitter suchthat the second light emitter illuminates the second light detector.